Coercivity of Sm(Co0.9Cu0.1)4.8 melt-spun ribbons

Structural and magnetic properties of melt-spun Sm(Co0.9Cu0.1)4.8 ribbons were investigated as a function of wheel surface speed. The ribbons melt-spun at 5 m/s contained a small volume fraction of secondary SmCo7 and Sm2Co7 phases in a SmCo5 matrix phase. The ribbons prepared at higher wheel surface speeds at 40 and 50 m/s were comprised of only the single phase SmCo5. A high coercivity of 42.6 kOe was obtained from the ribbon melt-spun at 50 m/s. The dependence of coercivity on melt-spinning was related to the constituent phases, grain size and domain wall pinning at grain boundaries.